A deceleration control apparatus for a vehicle disclosed in JP 2006059095A judges certainty of a vehicle being driven following a recommended route, which is figured out by the route guidance system, on the basis of, for example, a positional relationship between an intersection and the vehicle, vehicle behavior when the vehicle is approaching the intersection, and operational history of driving. Then the deceleration control apparatus for the vehicle executes an informing (alarming) operation and a deceleration control immediately after the vehicle passes the intersection based on the certainty of the vehicle being driven following the recommended route. In other words, when the recommended route is set by the route guidance system, the deceleration control apparatus preliminary obtains curve information of an interchange exit or a junction before the vehicle approaches to the intersection. Then, when the certainty of the vehicle increases, the deceleration control apparatus for the vehicle executes the informing operation or/and the deceleration control based on the curve information preliminary obtained immediately after the vehicle passes the intersection. The increases in the certainty of the vehicle mean increases in the certainty that the vehicle is driven towards the interchange exit or the junction following to the route guidance system.
In this configuration, the deceleration control apparatus disclosed in JP 2006059095A executes the informing operation and deceleration control quicker than any previous known. Further, the informing operation and the deceleration control are prevented from being improperly executed when a driver of the vehicle does not follow the recommended route and the vehicle is driven towards another route. Hence, it is conceivable that a side support portion may be controlled in the same manner as the deceleration control apparatus for the vehicle controls the informing operation and the deceleration control.
The deceleration control apparatus for the vehicle disclosed in JP2006059095A preliminary obtains the curve information of the recommended route when the vehicle is approaching the intersection. When the certainty of the vehicle being driven following the recommended route increases, the deceleration control apparatus immediately executes the informing operation or the deceleration control after the vehicle passes the intersection based on the curve information. However, the deceleration control apparatus disclosed in JP2006059095A may not prevent improper operations caused by distance errors generated because of accuracy of the curve information or vehicle location information.
A need thus exists for a seat apparatus for a vehicle which is not susceptible to the drawback mentioned above.